This book investigates the concept of freedom as it has been defined by Søren Kierkegaard and some of existentialism's major figures, including Jean-Paul Sartre. In an attempt to delineate an ontology of the human condition, special emphasis is placed on the ideas of choice, responsibility, and transcendence. The second part of the book focuses on existential freedom in what has been its most radical formulation by Sartre. A translation of Il sentimento paralizzante del possibile. La vertigine della libertà in Kierkegaard e Sartre (2022), this book brings cutting-edge contemporary Italian philosophy to English readers.